Over time or because of a particular event or condition (e.g., seismic activity, exposure to excessive or uneven loads or moments, poor compaction, crown corrosion, corrosive soil, etc.), the structural integrity or capacity of force mains, other pipes, and like structures may diminish. For example, such items may crack, corrode, deteriorate, and the like. Such damage to a pipe is particularly problematic when the pipe is used to carry a high pressure fluid because the pressurized fluid can impart significant forces, particularly in the hoop direction, on the pipe. Different methods of repairing or otherwise strengthening damaged pipes and other items are known. For example, fabric liners can be attached to one or more portions of a pipe interior. In cured-in-place pipe lining applications, such liners are impregnated in a curable resin or epoxy, attached to the interior surface of a host pipe, and allowed to cure, thereby forming a watertight barrier between the host pipe and the pipe interior.
Certain conventional cured-in-place pipe liners comprise random-oriented chopped glass fiber fabric. Those having ordinary skill in the art will appreciate that random oriented chopped fiber fabric has certain advantageous properties for cured-in-place pipe lining applications. The fabric has substantial void space providing for carrying a substantial amount of curable polymer that can be cured to form the finished pipe. Moreover, because the random oriented fibers are loosely secured to one another, the individual chopped fibers can move relative to one another, which allows the fabric to stretch as it is being installed in a host pipe to engage the inner wall of the pipe. This feature is advantageous because stretching a liner in the hoop direction as it is being installed in a host pipe helps prevent wrinkles from forming in the liner. By comparison, fabrics made of continuous fibers of the same material are less stretchable. But because the chopped fibers are arranged in a random orientation, the strength characteristics of the chopped fibers, particularly after being stretched are not maximized for pressure pipe lining applications. Examples of pressure pipes include sewer force mains and water pipes.